<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>A页面</title>
</head>

<body>
    <p>A页面</p>
    <input id="button" type="button" value="打开iframe" onclick="openIframe()" />
</body>
<script type="text/javascript" src="sdk_a.js"></script>
</html>